for the non signed routes, you can go with 'lcn=proposed' it will render as a dashed line in open cyclemap after a few weeks.

I used to put lcn=yes on ways, but lately, for longer routes with names, I've been using the relation editor.
In the potlatch tag editor, click the advanced tag, then on the bottom left, you will have a 'add to' link.. click 'add to' then 'new relation' then 'local cycling network' if it's a neighbourhood route, The Name of the route will be the route's name. the Reference will be the name it's rendered so you can call it Trans Canada Trail Cycle Route - and give it a reference of TCT
Then, to make the route longer, you add more segments to the cycle route relation. You can select multiple segments with CTRL-CLICK if your potlatch editor is behaving nicely and add multiple route segments at a time.

Wow thanks you guys are super helpful! I will use Alexz's suggestion to 'lcn=proposed' tag. I'm using an geo-referenced illustrator file in qGIS then shapefiles from OSM. and potlach.

Then end game is to use this in mapbox or leaflet for routeing via bike routes. Some areas are "suggested" bike routes, but no signage/paint exists. LCN=proposed may be perfect for this, while bike=yes

Please use route relations for the cycleway network, rather than tagging the underlying ways. It's much easier to maintain, allows for richer tagging on the related route, and all around less of a hassle to deal with.